Valve mechanism for air-compressors.



H. V. CONRAD. VALVE MECHANISM FOR 1113 OOMPRESSORS.

'Arrmonmfi FILED DBO.19, 1910. v 1

Batented May 19, 1914 WITNESSES INVENTOR rnnsrarrns PATENT orrioe.

HUGH-"V. CONRAD, or PITTSBURGH, PEN

NsrLvANIA, AssIeNon, TO THE WESTING- HOUSE AIR BRAKE COMPANY, OF PITTSBURGH, PENNSYLVANIA, A. CORPORATION or PENNSYLVANIA.

VALVE MECHANISM FOR AIR-COMPRESSORS.

Specif cation of Letters Patent. Application filed December 19, 1910.

Serial No. 598,077.

i. To all whom z'tmay concern Be it known that I, HUGH V. CONRAD, a

citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Valve Mechanism for Air-Compressors, of which the following is a specification.

This invention relates to the fluid inlet valve mechanism of a fluid compressor, and has reference more particularly to compres-v sors designed to run at high speeds, such, for example, as those driven by direct connectionto an. electric motor.

There are some advantages to be gained by the employment of a high speed corn pressor of the above character, such as d1spensing with reducinggears between motor and compressor crank shaft, the reduced size of motor required on account of the higher operating speed of the motor, and the increased capacity .of the compressor for a given size, due .to the higher operating speed of the'oompressor. It has, however, been found that the safe speed at which the compressor inlet valves may be operated is limited, owing to the liability at high speeds of the valves and valve stems breaking due I to the greater impact effect of the valves and the increased tendency at such speeds of the valve and valve stem material to crystallize and thus facilitate breakage of parts and furthermore, athigh speeds the valves can not act rapidly enough in the opening and closing movements by reason of the increased momentum of theparts.

The. principal object of my invention is to remedy this difficulty and for this purpose I proposet-o employ. two inlet valves for each compressor cylinder which are adapted to operate alternately, one opening on one suction stroke of the compressor and the other opening on the next suction stroke, so that the speed of each inlet valve is only onehalf' that of a single inlet valve under the same conditions and the speed of the inlet valves is thus reduced to; within safe, working limits. 1

- In the accompanying drawing,' Figure '1 is a sectional view taken substantially on the line ca of Fig. 2 of an air compressor with my improvement applied thereto andFig. 2

a front elevational view thereof, partly in section,

ends of the valve stems 9 As shown in the drawing, the compressor may comprise the usual casing 1 having an air cylinder 2 containing piston3 connected by rod at to the crank shaft 5, said crank shaft being connected up to an electric motor or other desired source of power;

The compressor cylinder is provided with the outlet valves 6, of the usualpuppet type,

tively. The fingers 18 and 19 are arranged to hear on the cam surfaces of the cams 12 and lilaud said cams are adjusted 180 degrees apart, so that one of the pins 16 and 17 is operated at each half revolution of the shaft The gear 14 and the pinion 15 are in theratio of two to one, so that the cam shaft 11 makes one revolution for every two revolutions of the crank shaft 5.

' It will now be evident that when the compressor is running, each inlet valve is operated only every other suction stroke of the compressor thus reducing the movements of each inlet valve to one half that of a singleinlet' valve applied to a compressor operating at the same speed and thereby minimizing the danger of valve breakages as well as securing a more etficient action of the valves. While a duplex or double cylinder air compressor is illustrated in the drawing, it will be understood that my,-improvement may be applied to compressors cylinders such as single stage and double stage or compound compressors.

Having now described my invention, what I claim as new and desire to secure by Leti ters Patent, is

1. The combination with sor cylinder, of two mlet valves for controlling the admission offluid to one end of the ing said valves at different times.

' 2. The combination with a fluid compres- Patented May 19, 1914.

having one or more with a pin- I Loosely. l are pins 16 and 17,

a fluid compres- 1 compressorcylinder and means for actuatvalves for controlling the admission of fluid to said cylinder at one end of the piston, and means for alternately actuating said inlet valves. i

. 4. The combination with a fluid compressor cylinder and a piston therein, of two in let valves for controlling the admission of fluid to the compressor cylinder at one end of thepiston and means for actuating each inlet valve on alternate suction strokes of the piston. I

5. The combination with a fluid compressor cylinder and a piston therein, of two inlet valves for controlling the admission of fluid to" the compressor cylinder at one end of the piston and means for actuatingsaid inlet valves inv alternate succession corresponding with the suction strokes of'the piston.

my hand; i I v I HUGH V. CONRAD.

WVitnesses: I 3 i A M. (ELEMENTS, Bl OLivER.

In testimony whereof I have hereunto set 

